Basic Server/DNS Question

I have read through some DNS literature and have a basic understanding of DNS and linux servers (still very new though) and one thing that I really do not understand is how the hostname and domain name relate to the setup of my mail server. Here is my layout:

My server name is pm04.cgroge.com

I set the hostname to this value pm04.cgroge.com

cgroge.com is fictional. I think this is right?

One of the domains I wish to server mail for is openbizguide.com

When setting up Zimbra the install will break and say that it cannot resolve the hostname. This confuses me because by using a fictional domain to setup my server it naturally would have no way to resolve the name!

Should I be using a derivitive of a real domain name to name my server? Should I instead use something like pm04.openbizbuide.com? (since openbizguide.com is resolvable)

You need the hostname set in the /etc/hosts file as per your comment above, if you are on a LAN you also need DNS A & MX records for it to work - it does not matter if the domain is fictional as long as it resolves to your LAN IUP of the server. Details here and herehttp://www.zimbra.com/docs/os/latest...stall/#1057019.